Shootings prompt outcry over social media

Three attackers posted on extremist site 8chan, which has remained offline

Shootings in two US cities this month that left 31 people dead and 53 wounded have set off a national outcry over the role of social media in distributing extremist content online.

The platforms' responsibilities have been debated in the news since the Aug 3 shooting at a Walmart store in El Paso, Texas, which killed 22 people, followed by an Aug 4 shooting in downtown Dayton, Ohio, in which 9 people including the shooter died.